Summary

The hermaphrodite (her) gene is necessary for sexual differentiation in Drosophila. Our characterization of her's zygotic function suggests that one set of female-specific terminal differentiation genes, the yolk protein (yp) genes, is transcriptionally activated by two separate pathways. One is a female-specific pathway, which is positively regulated by the female-specific doublesex protein (DSXF). The other is a non-sex-specific pathway, that is positively regulated by HER. The HER pathway is prevented from functioning in males by the action of the male-specific doublesex protein (DSXM). The HER and DSX pathways also function independently to control downstream target genes in the precursor cells that give rise to the vaginal teeth and dorsal anal plate of females, and the lateral anal plates of males. However, a female-specific pathway that is dependent on both DSXF and HER controls the female-specific differentiation of the foreleg bristles and tergites 5 and 6, and the male-specific differentiation of these tissues does not require the suppression of HER's function by DSXM.

Huntington's disease results in selective neurodegeneration in the forebrain and eventually death; there is currently no cure or therapy to slow its onset. Now, Ali Brivanlou and colleagues describe how isogenic stem cell lines with HTT repeat expansions give insights into the disease's cellular aetiology.

The resources pages of the Node and the BSDB have been combined and refurbished, with the new page designed to provide a range of useful links, including information on advocacy and outreach, new teaching resources for schools and databases for a wide range of species.